Exemplary embodiments of the present disclosure relate to battery management systems that may be used, for example, for managing power output and modes of one or more batteries in an electric vehicle.
An electric vehicle uses a battery pack as an energy source. To ensure that the electric vehicle operates properly, the battery pack is monitored and managed during discharge and charging, e.g. to maintain the battery pack within a certain range of temperature and other parameters. Operating within the working temperature ensures that the battery pack performs efficiently and has a long service life. Due to the large influence of temperature on the performance and the service life of the battery pack, the working temperature of the battery pack and the consistency of the working states of the battery cells within the battery pack are very important in the design of the electric vehicle and the battery pack. As such a battery management system (BMS) is typically used to manage the performance and operation of a rechargeable battery (e.g. a cell or battery pack), by protecting the battery from operating outside its working temperature, monitoring its state, and calculating and/or reporting data to other control systems in the vehicle. The BMS may also control recharging of the battery, e.g. by redirecting recovered or charger energy to the battery pack.
When an electrical vehicle is turned off, may maintain operation of at least some electrical subsystems that slowly drain the battery. This can result, for example, in “leakage” of 13 mA-4 mA of current from the battery.